ceph/src/boost/boost/hana/fwd/is_disjoint.hpp

   1 /*!
   2 @file
   3 Forward declares `boost::hana::is_disjoint`.
   4
   5 @copyright Louis Dionne 2013-2017
   6 Distributed under the Boost Software License, Version 1.0.
   7 (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
   8  */
   9
  10 #ifndef BOOST_HANA_FWD_IS_DISJOINT_HPP
  11 #define BOOST_HANA_FWD_IS_DISJOINT_HPP
  12
  13 #include <boost/hana/config.hpp>
  14 #include <boost/hana/core/when.hpp>
  15
  16
  17 BOOST_HANA_NAMESPACE_BEGIN
  18     //! Returns whether two `Searchable`s are disjoint.
  19     //! @ingroup group-Searchable
  20     //!
  21     //! Given two `Searchable`s `xs` and `ys`, `is_disjoint` returns a
  22     //! `Logical` representing whether the keys in `xs` are disjoint from
  23     //! the keys in `ys`, i.e. whether both structures have no keys in common.
  24     //!
  25     //!
  26     //! @param xs, ys
  27     //! Two `Searchable`s to test for disjointness.
  28     //!
  29     //!
  30     //! Example
  31     //! -------
  32     //! @include example/is_disjoint.cpp
  33 #ifdef BOOST_HANA_DOXYGEN_INVOKED
  34     constexpr auto is_disjoint = [](auto const& xs, auto const& ys) {
  35         return tag-dispatched;
  36     };
  37 #else
  38     template <typename S1, typename S2, typename = void>
  39     struct is_disjoint_impl : is_disjoint_impl<S1, S2, when<true>> { };
  40
  41     struct is_disjoint_t {
  42         template <typename Xs, typename Ys>
  43         constexpr auto operator()(Xs&& xs, Ys&& ys) const;
  44     };
  45
  46     constexpr is_disjoint_t is_disjoint{};
  47 #endif
  48 BOOST_HANA_NAMESPACE_END
  49
  50 #endif // !BOOST_HANA_FWD_IS_DISJOINT_HPP